1. Technical Field
The present invention relates generally to an appliance for electrical tests, and more particularly to a testing jig.
2. Description of Related Art
To check electrical connections between precision electronic components in an electronic product, probe cards are widely used as a communication interface for test signals and power signals transmitted between a test machine and a device under test (DUT). A probe card is mainly constructed by a plurality of probes and a rigid multilayer printed circuit board. By contacting a tested portion on a DUT with tips of the probes to transmit test signals thereto, electrical tests can be performed on the DUT.
With the advances in electronic technology, the processing speed of the DUT and signal transmission capacity per second increases, and therefore the frequency of test signals outputted by a test machine also rises. However, probes are quite slender, and the distance between every two neighboring probes is usually arranged in a linear way, which causes higher inductance. Though the amount of inductance is still small, it greatly increases the resistance of the circuit while transmitting test signals in high frequency, which greatly attenuates test signals with high frequency, and consequently, leads to false reading of test signals.